Heretofor, a variety of types of accumulating conveyor systems have been used, some of which employ a series of carrier rollers, for example, U.S. Pat. Nos. 3,650,376; 4,133,425; and 4,148,391, while others utilize parallel rows of roller chains which support and transport cartons or other types of loads, for example, U.S. Pat. Nos. 3,056,483; and 3,690,439. Still other systems incorporate "walking beam" type arrangements wherein articles are moved intermittently in stepwise fashion from a first station to a second station with provisions for varying the spacing between articles for precise positioning thereof, for example, U.S. Pat. No. 3,970,008, or with provisions for accumulating the articles for individual or group transfer, for example, U.S. Pat. No. 3,565,241.